Alan Turing but that is in the works anyway.

She's a dog. It should be Rebecca Black instead.

Mayor West

Any historical figure who is not a dead white male. Please and thanks. Native American figure? African American figure?

Why do new US banknotes still look ancient?

Royalty and people who have done outstanding and exception things for the betterment of the country (not fictional characters and nothing for the purposes of making a political statement - something that stands the test of time).

I'd like to see Heinrich Heine on the 20€ bill. But it would be only paperback fame. Not the real one.

Obama. Just the proposal of it. I figure it would probably give a heart attack to at least 25% of conservatives

Someone who better represents the whole vibe, like the Walmart Smiley Face. Or the Starbucks Mermaid, except with a shirt on that says "All Lives Matter."

Mr. Clean

I doubt anyone I respected like that would want to have their face on American currency considering what it represents, I kinda wonder how Harriet would feel about it TBH